Primary Intracranial Ewing Sarcoma Invading the Superior Sagittal Sinus with EWSR1-FLI1 Gene Fusion and EWSR1 Gene Mutation: A Case Report and Literature Review

BACKGROUND

Primary intracranial Ewing sarcoma (ES) is an extremely rare intracranial malignant tumor, mostly occurring in children and adolescents. Because of its rarity, the magnetic resonance imaging (MRI) features and treatment strategies of primary intracranial ES are still unclear.

METHODS

The purpose of this study was therefore to report a case of primary intracranial ES, whose molecular features included both EWSR1-FLI1 (EWS RNA binding protein 1- Friend leukemia integration 1) gene fusion and EWSR1 gene mutation. It is worth noting that this is the first reported case of ES invading the superior sagittal sinus and mostly causing occlusion. At the same time, there were polymorphisms of four drug metabolism-related enzymes in the tumor. Subsequently, we conducted a literature review to characterize the clinical features, imaging findings, pathological features, treatments, and prognoses of primary intracranial ESs.

RESULTS

A 21-year-old female was admitted to the hospital with headache with nausea and vomiting for 2 weeks. An MRI showed a 3.8 × 4.0 cm large heterogeneous mass in the bilateral parietal lobe with peritumoral edema. The tumor invaded the superior sagittal sinus and mostly caused occlusion of the middle segment of the superior sagittal sinus. The mass was successfully removed using a neuromicroscope. Postoperative pathology indicated a primary intracranial ES. High throughput sequencing (next generation sequencing) showed that there was EWSR1-FLI1 gene fusion and EWSR1 gene mutation in the tumor, with polymorphisms of four drug metabolism-related enzymes and low tumor mutational burden. Subsequently, the patient received intensity modulated radiation therapy. The patient has signed an informed consent form.

CONCLUSIONS

The diagnosis of primary intracranial ES depended on histopathology, immunohistochemistry staining, and genetic testing. At present, total tumor resection combined with radiotherapy and chemotherapy is the most effective treatment. We report the first case of primary intracranial ES invading the superior sagittal sinus and causing middle segment occlusion, accompanied by EWSR1-FLI1 gene fusion and EWSR1 gene mutation.

Malignant spindle cell tumors of the posterior fossa in children: case series and review of management

OBJECTIVE

The WHO Classification of Tumours of the Central Nervous System (2016) classifies nonmeningothelial malignant spindle cell tumors involving the extraaxial tissues of the posterior fossa as melanocytic tumors and malignant mesenchymal tumors (sarcomas). The objective of this study was to conduct a review of the literature pertaining to the management strategies of posterior fossa malignant spindle cell tumors in the pediatric population.

METHODS

The authors performed an institutional search of their pathology database for patients younger than 18 years of age who presented with posterior fossa malignant spindle cell tumors. A literature review was also performed using the PubMed database, with "posterior fossa" or "spindle cell tumors" or "Ewing sarcoma" or "high-grade" or "spindle cell sarcoma" or "leptomeningeal melanocytoma" as keywords. The database search was restricted to pediatric patients (age ≤ 18 years). Parameters reported from the literature review included patient age, tumor location, presenting symptoms, treatment modalities (resection, chemotherapy, and/or radiotherapy), leptomeningeal spread at or after the time of treatment, and follow-up length and resulting outcome.

RESULTS

The authors report 3 rare cases of posterior fossa malignant spindle cell tumors, including Ewing sarcoma in a 13-year-old male; high-grade spindle cell sarcoma, not otherwise specified in a 10-year-old male; and primary leptomeningeal melanocytoma in a 16-year-old female. All 3 patients underwent resection and radiotherapy and either chemotherapy or targeted immunotherapy. At the last follow-up, all patients were alive with either resolution or stable disease.

CONCLUSIONS

A review of these 3 cases and the existing literature support managing patients with intracranial malignant spindle cell tumors with multimodal therapy that can include a combination of resection, radiotherapy, and chemotherapy or immunotherapy to prolong progression-free and overall survival.

Primary intracranial Ewing sarcoma/ peripheral primitive neuroectodermal tumor, an entity of unacquaintance: a series of 8 cases

PURPOSE

The purpose is to highlight the primary intracranial (meningeal-based) occurrence of Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET).

METHODS

This report is a collation of clinicopathological features of eight cases of molecularly and clinicoradiologically confirmed primary (non-metastatic) intracranial (non-osseous) meningeal ES/PNET.

RESULTS

The age range was 1 to 33 years with a median age of 9 years. Male to female ratio was 0.6:1. All patients were diagnosed on the debulking surgical material (gross total resection, 2 cases; subtotal resection, 6 cases) and showed primitive embryonal histomorphology with diffuse membranous CD99 immunoexpression and EWSR1 gene rearrangement by fluorescence in situ hybridization. Seven of them showed a typical FISH pattern of split signals with break-apart probe, while one showed an unusual signal pattern of loss of green signals. EFT-2001 adjuvant protocol was followed along with focal radiotherapy (RT) in all cases (except case 8, full course of chemotherapy could not be completed). Two cases had local recurrence-one of them died of disease recurrence before the administration of further treatment.

CONCLUSION

This series adds non-osseous intracranial site to the list of uncommon sites of occurrence for ES/PNET and more importantly emphasizes the need to be considered in a differential list of primary intracranial primitive embryonal tumors before embarking as primary central nervous system (CNS) embryonal tumor, NOS.

The spectrum of rare central nervous system (CNS) tumors with EWSR1-non-ETS fusions: experience from three pediatric institutions with review of the literature

The group of CNS mesenchymal (non‐meningothelial) and primary glial/neuronal tumors in association with EWSR1‐non‐ETS rearrangements comprises a growing spectrum of entities, mostly reported in isolation with incomplete molecular profiling. Archival files from three pediatric institutions were queried for unusual cases of pediatric (≤21 years) CNS EWSR1‐rearranged tumors confirmed by at least one molecular technique. Extra‐axial tumors and cases with a diagnosis of Ewing sarcoma (EWSR1‐ETS family fusions) were excluded. Additional studies, including anchored multiplex‐PCR with next‐generation sequencing and DNA methylation profiling, were performed as needed to determine fusion partner status and brain tumor methylation class, respectively. Five cases (median 17 years) were identified (M:F of 3:2). Location was parenchymal (n = 3) and undetermined (n = 2) with topographic distributions including posterior fossa (n = 1), frontal (n = 1), temporal (n = 1), parietal (n = 1) and occipital (n = 1) lobes. Final designation with fusion findings included desmoplastic small round cell tumor (EWSR1‐WT1; n = 1) and tumors of uncertain histogenesis (EWSR1‐CREM, n = 1; EWSR1‐CREB1, n = 1; EWSR1‐PLAGL1, n = 1; and EWSR1‐PATZ1, n = 1). Tumors showed a wide spectrum of morphology and biologic behavior. For EWSR1‐CREM, EWSR1‐PLAGL1 and EWSR1‐PATZ1 tumors, no significant methylation scores were reached in the known brain tumor classes. Available outcome (4/5) was reported as favorable (n = 2) and unfavorable (n = 2) with a median follow‐up of 30 months. In conclusion, we describe five primary EWSR1‐non‐ETS fused CNS tumors exhibiting morphologic and biologic heterogeneity and we highlight the clinical importance of determining specific fusion partners to improve diagnostic accuracy, treatment and monitoring. Larger prospective clinicopathological and molecular studies are needed to determine the prognostic implications of histotypes, anatomical location, fusion partners, breakpoints and methylation profiles in patients with these rare tumors.

Primary Intracranial pPNET/Ewing Sarcoma: Diagnosis, Management, and Prognostic Factors Dilemma-A Systematic Review of the Literature

BACKGROUND

Ewing sarcoma (ES) is a malignant bone tumor that is most commonly observed in the long bones, the pelvis, and the chest. Primary intracranial localization is extremely rare.

OBJECTIVE

In the aim of identifying the prognostic factors of this rare localization, we conducted a systematic review of the literature for patients with primary intracranial peripheral primitive neuroectodermal tumor/ES.

METHODS

A complete MEDLINE search was undertaken for all articles reporting data for primary intracranial peripheral primitive neuroectodermal tumor/ES. We divided the patient population into 2 groups: group I, patients who were free of disease; and group II, patients who died or had uncontrolled disease at the last available follow-up. We conducted a comparative statistical analysis of data between the 2 groups.

RESULTS

A total of 48 patients were included in the review. There were 32 patients in group I and 12 in group II. Fifty percent of tumors in group II and only 16% of tumors in group I were infratentotorial (P = 0.03). Signs of bone involvement were observed in 19% of patients in group I and 54% in group II (P = 0.03). Total removal was accomplished in 29% of patients in group I and in no patients in group II (P = 0.03). Radiotherapy was performed in 73% of patients in group II and 81% in group I (P = 0.43). Chemotherapy was administered in 36% of patients in group II and 74% in group I (P = 0.03).

CONCLUSIONS

Infratentorial localization and the presence of bone involvement were associated with poor prognosis; Surgery seems to be a predictive factor of prognosis; radiotherapy and chemotherapy must be performed whenever the tumor is not totally removed.

First Case of Primary Sellar/Suprasellar-Intraventricular Ewing Sarcoma: Case Report and Review of the Literature

BACKGROUND

Intracranial Ewing sarcoma (ES) and peripheral primitive neuroectodermal tumors (pPNETs) are extremely rare and poorly differentiated neoplasms. Immunohistochemical and cytogenetic findings support the possibility of a unique nosologic entity. Primary intracranial localization of this tumor is extremely rare; a few cases are reported in the literature, with only some confirmed by genetic studies.

CASE DESCRIPTION

We report a 12-year-old patient with a sellar/suprasellar mass with intraventricular extension that in all its features mimicked a transinfundibular craniopharyngioma. The patient underwent complete resection of the lesion via an endoscopic endonasal transtuberculum approach 6 days after ventriculoperitoneal shunt for acute obstructive hydrocephalus. Histopathologic and genetic examination demonstrated ES/pPNET. The diagnosis was confirmed by detection of a rearrangement of the EWSR1 gene by fluorescent in situ hybridization and identification of the diagnostic t(11;22) translocation by reverse transcriptase polymerase chain reaction. The patient remained in complete clinical remission 12 months after tumor resection followed by adjuvant chemotherapy with no radiologic evidence of tumor recurrence.

CONCLUSIONS

To our knowledge, this is the first case of primary intrasellar/suprasellar-intraventricular ES/pPNET confirmed by molecular genetic analysis. Extensive investigations, including pathologic, immunohistochemical, and genetic studies, are needed for differentiation of these tumors from other, more common sellar/suprasellar tumors. Our case highlights that an interdisciplinary therapeutic approach is mandatory to guarantee a favorable outcome.

Epileptic seizure in primary intracranial sarcoma: a case report and literature review

PURPOSE

The aim of this study is to describe epileptic seizures in patients with primary intracranial sarcomas.

METHODS

We report a 17-year-old girl diagnosed with primary high-grade intracranial sarcoma with initial clinical manifestation of nonconvulsive status epilepticus. Literature reports between 2000 and 2014, relevant to primary intracranial sarcomas in children, were reviewed. The clinical presentations and neurological outcomes were analyzed.

RESULTS

Eleven of 29cases (38 %), 8 males and 3 females, who exhibited epileptic seizures as one of the initial symptoms and diagnosed with primary intracranial sarcomas were collected. The median age of disease onset was 5 years. The two most common seizure types were generalized seizures (45 %) and status epilepticus (36 %). Nine of 11 patients (82 %) had tumor growth involving the frontal lobe. Nine cases had the median duration of follow-up 1.7 years, of which 6 cases showed tumor recurrence and 3 cases died during the period of follow-up.

CONCLUSIONS

Epileptic seizures as one of the clinical manifestations are uncommon. The two most common seizure types were generalized seizures and status epilepticus. The most frequent location of primary intracranial sarcoma-related seizures was the frontal lobe. The clinical outcome varied.

Ewing sarcoma of the posterior fossa in an adolescent girl

Medulloblastoma, astrocytoma, and ependymoma represent the most common infratentorial tumors in childhood, while Ewing sarcomas in that localization are extremely rare. A large left infratentorial space-occupying lesion was diagnosed in a 12-year-old girl with signs of increased intracranial pressure. Following total tumor resection, histological and molecular examination revealed Ewing sarcoma with rearranged EWSR-1 gene. The patient achieved complete remission following adjuvant chemotherapy and radiotherapy according to Euro-EWING 2008 treatment protocol. Intracranial Ewing sarcoma, although rare, should be an important differential diagnosis of intracranial tumors in childhood which requires aggressive multimodal treatment.

What's in a name? Intracranial peripheral primitive neuroectodermal tumors and CNS primitive neuroectodermal tumors are not the same

BACKGROUND

Intracranial peripheral primitive neuroectodermal tumors (P-PNET) are extremely rare. They can be easily misdiagnosed as central nervous system primitive neuroectodermal tumors (CNS-PNET) or meningiomas. Little is known about the optimal treatment and prognosis of these tumors.

PATIENTS AND METHODS

We evaluated the treatment and outcome of 17 patients with intracranial, nonmetastatic, genetically confirmed P-PNET. Three patients were treated at our institutions. Thirteen other cases providing sufficient treatment and follow-up information were extracted from the literature.

RESULTS

The median age at diagnosis was 17 years. All patients underwent initial surgery. Complete resection was achieved in 9 of the 17 cases (53 %). Combined adjuvant treatment consisting of radiotherapy (focal, n = 10; craniospinal, n = 1) and chemotherapy was administered to 11 of the 17 patients (59 %). The median follow-up time was 1.4 years. In 8 of the 17 patients (47 %), the disease progressed; 4 of the 17 patients (24 %) died. The 2-year progression-free and overall survival rates were 64 % and 76 %, respectively.

CONCLUSION

The differential diagnosis for intracranial, meningeal-based, small, round-cell tumors should include P-PNET. It is highly probable that complete resection has a positive impact on survival--as previously reported for extracranial P-PNET--but this cannot be shown by our data. Intensive adjuvant treatment consisting of radiotherapy and chemotherapy seems to be essential. A statistically grounded recommendation for the appropriate target volume and radiation dose is not yet possible. However, in most case reports of primary intracranial P-PNET published to date, patients were treated with focal irradiation. The optimal chemotherapy regimen has yet to be established, with both the Ewing tumor and CNS-PNET protocols being promising candidates for effective treatment.

Disseminated Intracranial Ewing's Sarcoma in an Adult: A Rare and Difficult Diagnosis

The Ewing sarcoma family of tumors comprises a rare class of cancers of mesenchymal origin. Cases of Ewing's sarcoma in the central nervous system – specifically, intracranial Ewing's – are extremely rare. Almost all reported cases have occurred in children. However, this rare presentation can also occur in the adult population. It is important to distinguish these tumors from primitive neuroectodermal tumors at the time of diagnosis. Testing for EWSR1(22q12) gene rearrangement using fluorescence in situ hybridization is a useful tool for making the distinction between these 2 similar but distinct entities. We present here the case of a middle-aged male patient with intracranial Ewing's sarcoma, and discuss diagnostic challenges and potential new treatment approaches for this rare disease.

Analysis of prognostic factors in extraosseous Ewing sarcoma family of tumors: review of St. Jude Children's Research Hospital experience

BACKGROUND

Advances in the treatment of Ewing sarcoma family of tumors (ESFT) are the result of improvements in systemic and local therapies. Clinical data of extraosseous ESFT are scarce.

METHODS

A retrospective analysis of all patients with extraosseous ESFT treated at St. Jude Children's Research Hospital (SJCRH) from June 1982 to August 2009.

RESULTS

Forty-six patients with extraosseous ESFT were identified. The mean age at diagnosis was 13.8 years. The majority of patients were male and white. The most common site of primary tumor was the trunk. Twelve patients had subcutaneous tumors. The median tumor size was 8 cm. Six patients (13 %) had metastatic disease at diagnosis. A total of 59 % of patients were alive at the time of analysis, with a median follow-up from diagnosis of 15.3 years. Fifteen-year estimates of survival and event-free survival (EFS) for all patients were 53.3 ± 9.4 and 50 ± 9.1 %, respectively. Fifteen-year estimates of survival and EFS with localized disease were 61.4 ± 9.8 and 57.6 ± 9.7 %, respectively. Stage and subcutaneous ESFT were significant predictors of outcome. There was no significant difference in patient's demographics and tumor characteristics between patients with skeletal ESFT and extraosseous Ewing sarcoma. The outcome for patients with localized extraosseous Ewing sarcoma was similar to that reported for all localized ESFT patients treated at SJCRH.

CONCLUSIONS

The outcome for localized patients treated with extraosseous ESFT was similar to that reported for all ESFT patients treated on protocols at SJCRH. Patients with subcutaneous ESFT had a favorable prognosis when compared to their counterparts.

Primary intracranial Ewing sarcoma with an unusually aggressive course: a case report and review of the literature

The occurrence of Ewing sarcoma-peripheral primitive neuroectodermal tumor as a primary intracranial tumor is very rare, with only 29 cases reported in the literature, 19 of which have included molecular studies. We present the clinical, radiologic and pathologic findings of an intracranial Ewing sarcoma in a 22-year-old woman arising from the dura over the right frontal convexity. The patient underwent craniotomy with gross total excision of the tumor. The tumor showed atypical histology and the diagnosis was confirmed by detection of a rearrangement of the EWSR1 gene by fluorescent in situ hybridization and identification of the diagnostic t(11;22)(q24;q12) translocation by reverse transcription-polymerase chain reaction. Additional features were detected in this tumor that are known to be associated with an unfavorable prognosis, including loss of p16 expression and gains of chromosomes 1q and 12. The patient experienced the most rapid downhill course reported to date for intracranial Ewing sarcoma, developing multiple extracranial metastases at 2 months and dying 6 months after the initial operation.